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\textbf{Use Case S1:  Detailed Description}\\\\
Use Case Name:  Monitor Temperature Data\\
Scenario: N/A\\
Brief Description:  With the System running, the System monitors the
temperature data by periodically requesting raw temperature
information from the 1-wire temperature sensor.\\
Actors:  System\\
Related Use Cases:\\
\textbf{Use Case A1:} \emph{The Administrator shall set the
Measurement Rate for all active hardware sensors}\\
\textbf{Use Case S6: }\emph{The System Shall Save Temperature
data}\\
\textbf{Use Case S7: }\emph{The System Shall Save Temperature
Extremes}\\
\textbf{Use Case S9: }\emph{The System Shall Monitor and Save
Temperature Extremes}\\
\textbf{Stakeholders:  } Local and National Weather Bureaus, User
other systems and individuals monitoring local weather data.\\
\textbf{Preconditions:  } The System is running, the Measurement
rate is set, the network is set and working the thermometer hardware
is connected to the network.\\
\textbf{Postconditions:  } The Raw Temperature data is received from
the thermometer hardware, the raw data is converted into actual
temperature data.  The temperature is converted into the appropriate
units (Celsius, Fahrenheit, Kelvin).\\\\
\textbf{Flow of Events}\\
\begin{tabular}{|l|l|}\hline
\textbf{System} & \textbf{One Wire Temperature Sensor}\\\hline
1. Periodically request raw temperature \\
data from the One Wire Temperature \\ 
Sensor &
2. Returns the raw temperature data\\\hline
3. Converts the raw sensor data into\\the appropriate scales:
Celsius, \\Fahrenheit, Kelvin
 \\\hline
\end{tabular}\\\\
\textbf{Exception Conditions}\\
2.  If the One Wire Temperature Sensor returns an error, then
the system shall handle the error and report a default
temperature (-999.9$^\circ$).\\
2.  If the One Wire Temperature sensor stops working (drops out),
the the system shall report an error and display a default
temperature value (-999.9$^\circ$).\\
2.  If the One Wire network breaks, then the system shall report an
error and display default temperature value (-999.9$^\circ$).
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